The objectives are to investigate the methylation of tRNA in cells undergoing viral replication and/or transformation. Utilizing the unique features of affinity chromatography (antibody columns), tRNA populations will be separated on the basis of their content of methylated constituents and subsequently assessed in terms of establishing a definitive relationship between viral-induced cell transformation and aberrant modification of tRNA. Columns containing conjugated antibodies specific for the methylated constituents of tRNA will be prepared and assessed in terms of their ability to selectively retain or elute particular tRNA populations based on their content of methylated constituents. The presence of a hypermethylated tRNA in viral-infected cells will be established by its ability to be differentially fractionated from its normal tRNA counterpart (in uninfected cells) on antibody columns. Aminoacylation of these antibody-fractionated tRNA populations will establish the presence of a hypermethylated tRNA. Subsequent RPC-5 chromatography of this aberrant tRNA (in its charged form) will identify the particular isoaccepting species involved while subfraction on secondary antibody columns will aid in its purification. In an almost analogous manner, the specificity of tRNA methylases in viral-infected and uninfected cells will be characterized by separating heterologous tRNA substrates following their hypermethylation in vitro. Dependency of aberrant tRNAs to translate viral- and host-proteins will be attempted in cell-free, tRNA-dependent, translational systems.